if you do it right you will gain fitness. it's like sharpening the tip of the pyramid. winter was laying the foundation and summer is periods of sharpening the point. when i'm at my fastest i'm riding ten to fifteen hours plus races a week. 3/4 of it is above threshold. 1/4 is like sleeping snail.

then you write some checks with the sharp point until it gets dull.. and it takes more work to sharpen it... harder intesity.. shorter rides. intervals that make you almost lose consciousness. at my age i can sharpen it maybe three times in a spring/summer.

mixed metaphors. i'm still very slow at my sharpest.